1. Field of the Invention
The present invention relates to a method and to a circuit arrangement for generating setting signals for signal generators of a traffic signal system, particularly of a street traffic signal system, upon employment of indications of time intervals between mutually hostile traffic flows contained in a time interval matrix.
2. Description of the Prior Art
A method and a device for securing the time intervals in street traffic signal systems is known in the art from German patent application P 27 39 616.3. In this known method and device, at the end of the green interval of each individual signal of the traffic flows to be automatically controlled, the time elapsing from that point on is summed in actual value memories. These actual value memories are compared to the reference value memories of the traffic flows which are hostile to the green signal and, when the prescribed values are achieved or, respectively, exceeded, the appertaining activation command is transmitted. Moreover, all reference value memory contents are summed in a further actual value memory at shorter intervals than corresponds to the time clock of the traffic signal system, the content of the further actual value memory being compared to the content of a reference value memory. Upon occurrence of an error, appropriate safety measures are triggered. Thereby, however, an activation command for activating a green signal is only given to the respective signal generator in response to a corresponding selection by a central control when it has been determined by means of a coincidence check that the respectively prescribed clearing time (i.e. the time intervals since the respective end of green) have terminated in all signal groups which are hostile to the group belonging to the respective signal generator. The control signals, for example the so-called red command, required for the activation of the respective signal generator given end of green, however, become directly effective from the central control transmitting such signals, i.e. immediately at the signal generator respectively coming into consideration. This, however, means that signal generators are already set to red in a disadvantageous manner which could per se have still remained set to green, at any rate with respect to the signal generators subsequently receiving green commands. Therefore, only a relatively poor exploitation of the clearing times actually available is achieved overall in the method heretofore known.